Present studies were carried out to investigate the life history of potato tuber moth, Phthorimaea operculella (Zeller), under laboratory conditions in Suweon. Studies on its life-cycle on stored potato tubers in the laboratory showed that seven generations were reared in a year and the development from egg to adult was completed in an average of 49.4 days in spring at $18.2^{circ}C$., 21 days in summer at $26.8^{circ}C$., 26.1 days at $24.2^{circ}C$., and 39 days in autumn at $19.6^{circ}C$. The females laid an average of 101 eggs each, with a maximum of 242 and longevity of adults 17.6 days in spring at $15.1^{circ}C$., 8.1 days in May-September at $25.3^{circ}C$., and 13.3 days in autumn at $16.8^{circ}C$.